The concept of stress pervades modern society, with relief from it promised on everything from vitamin to vacation packages. Yet there exists no generally accepted classification of stressful experience, nor is the concept itself universally considered a valid subject for research. This authoritative work is the first to analyze critically the entire range of research and theory on stress in animals and humans, from the earliest studies in the 1930s up to the present day. Herbert Weiner not only documents the many empirical and conceptual advances of recent years, but also supplies a new working definition and classification of stressful experience. He describes the integrated, organismic responses to stressful environmental changes, tasks, and challenges in terms of functional adaptation: the failure of these responses results in injury, ill-health, disease, and death. To examine the coordination between behavior and bodily functions, Weiner reviews current knowledge on how stressful experiences also alter biobehavioral rhythms. Providing a useful, integrative concept of stress rooted in an understanding of the organism as an interactive communication system composed of many subsystems, Perturbing the Organism will interest a wide range of clinicians and researchers throughout the medical and behavioral sciences. The John D. and Catherine T. MacArthur Foundation Series on Mental Health and Development